4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chao Yu <yuchao0@xxxxxxxxxx> [ Upstream commit 27319ba4044c0c67d62ae39e53c0118c89f0a029 ] Thread GC thread - f2fs_ioc_start_atomic_write - get_dirty_pages - filemap_write_and_wait_range - f2fs_gc - do_garbage_collect - gc_data_segment - move_data_page - f2fs_is_atomic_file - set_page_dirty - set_inode_flag(, FI_ATOMIC_FILE) Dirty data page can still be generated by GC in race condition as above call stack. This patch adds fi->dio_rwsem[WRITE] in f2fs_ioc_start_atomic_write to avoid such race. Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/f2fs/file.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1512,6 +1512,8 @@ static int f2fs_ioc_start_atomic_write(s inode_lock(inode); + down_write(&F2FS_I(inode)->dio_rwsem[WRITE]); + if (f2fs_is_atomic_file(inode)) goto out; @@ -1532,6 +1534,7 @@ static int f2fs_ioc_start_atomic_write(s if (ret) clear_inode_flag(inode, FI_ATOMIC_FILE); out: + up_write(&F2FS_I(inode)->dio_rwsem[WRITE]); inode_unlock(inode); mnt_drop_write_file(filp); return ret;
